life expectancy vs expectancy

life expectancy and expectancy both are nouns.

Word	Noun	Adjective	Verb	Adverb
life expectancy	Yes	No	No	No
expectancy	Yes	No	No	No

As nouns, expectancy is a hypernym of life expectancy; that is, expectancy is a word with a broader meaning than life expectancy:

life expectancy: an expected time to live as calculated on the basis of statistical probabilities
expectancy: something expected (as on the basis of a norm)

Other hypernyms of life expectancy include anticipation.

life expectancy (noun)	expectancy (noun)
an expected time to live as calculated on the basis of statistical probabilities	something expected (as on the basis of a norm)
	an expectation